POS1164 CLINICAL OUTCOMES OF ANCA-ASSOCIATED VASCULITIS PATIENTS RECEIVING RITUXIMAB INDUCTION AND MAINTENANCE THERAPY: SYSTEMATIC REVIEW AND META-ANALYSIS OF LARGE OBSERVATIONAL STUDIES
Authors: X. Y. Yin, Y. R. Shi, Y. Shi, J. X. Zhang, C. S. Jing, X. X. Zheng, Q. Y. Su, Q. Yu, P. F. He, X. LI, S. X. Zhang
Journal: Annals of the Rheumatic Diseases (2023)

<h3>Background</h3> Rituximab(RTX), an anti-B-cell biological therapy, has been investigated in several clinical trials on antineutrophil cytoplasmic antibody (ANCA)-associated vasculitides (AAV). RTX achieved high remission induction and sustained maintenance rates in patients with severe AAV, thereby challenging the cornerstone treatment of corticosteroids and cyclophosphamide followed by azathioprine[1][2]. In past clinical studies, RTX has been observed to be associated with a considerable number of adverse events, although the remission rate is high. <h3>Objectives</h3> This study aimed to study the efficacy and side effects of RTX in the treatment of AAV to provide help for drug selection and the care of AAV patients. <h3>Methods</h3> We systematically searched PubMed, EMBASE, Web of Science, Medline, Wanfang database, VIP, CNKI, and CBM databases from the establishment of the database to January 10, 2023. Cohort studies and case-control studies were included in the meta-analysis. We used the rate of all-cause death, remission and recurrence as the primary outcome for evaluating efficacy and safety. Severe infection and organ involvement(including urinary, cardiovascular, digestive, respiratory, nervous, ear, nose, throat, and skin) were secondary outcome indicators. <h3>Results</h3> A total of 90 cohort studies, including 17,929 patients with AAV treated with RTX, were included in our study. The summary results indicated a 9.6%(95%CI: 0.071-0.123) risk of all-cause death in patients with AAV treated with RTX. Symptoms were relieved in 84.9%(95%CI: 0.803-0.890) of patients with medication, 41.4%(95%CI: 0.353-0.475) with complete remission and 45.0%(95%CI: 0.401-0.498) with partial remission. 10.7%, 14.2%, and 26.0% of patients faced disease recurrence in 6 months, 12 months, and 24 months respectively. Further, to compare the efficacy of RTX in the phase of induced remission and maintenance treatment, we conducted a subgroup analysis. The studies of accessible treatment stage were included. The results showed that RTX therapy during maintenance treatment presented lower all-cause mortality(5.4% vs. 9.1%) and a higher remission rate(86.1% vs.77.7%). For secondary results, RTX has a significant impact on all systems. The frequency of severe infection in patients treated with RTX was 25.6%(95%CI: 0.187-0.325). Ear, nose, and throat were the earliest and most affected organs(ES=57.7%, 95%CI: 0.433-0.721), and gastrointestinal diseases were the least common(ES=6.3%, 95%CI: 4.2%-8.5%). <h3>Conclusion</h3> Our results showed that using RTX in the treatment of AAV is efficacy, especially during maintenance treatment. Prevention should be carried out for different organ systems as early as possible to achieve personalized treatment. <h3>References</h3> [1]Guillevin, L. et al. Rituximab versus azathioprine for maintenance in ANCA-associated vasculitis. N Engl J Med 371, 1771-1780, doi:10.1056/NEJMoa1404231 (2014). [2]Raffray, L. &amp; Guillevin, L. Rituximab treatment of ANCA-associated vasculitis. Expert Opin Biol Ther 20, 899-910, doi:10.1080/14712598.2020.1748597 (2020). <h3>Acknowledgements:</h3> NIL. <h3>Disclosure of Interests</h3> None Declared.